SEMIANALYTICAL MONTE-CARLO METHOD AND SIMULATIONS OF EXTREMELY HIGH-ENERGY ELECTROMAGNETIC AIR SHOWERS

A rapid growth of a computational time with a primary particle energy is one of the most important problems arising with the Monte Carlo sim ulations of extremely high energy electromagnetic cascades. A new appr oach the semianalytical Monte Carlo (SAMC) method - is proposed to res olve this problem. The SAMC method provides a rather weak (logarithmic ) dependence of the computational time on the cascade primary energy a nd can be effectively used for the simulations in a broad primary ener gy extent far beyond 10(16) eV. The extended simulations of the differ ent characteristics of ultra high energy electromagnetic air showers h ave proved the accuracy and effectiveness of the SAMC method.